Related papers: Electron screening and its effects on Big-Bang nuc…
I present a review of Big Bang Nucleosynthesis, concentrating on the statistical analysis of theoretical uncertainties, and on systematic errors in observed abundances. Both have important implications for constraints on the amount of…
The pattern of nucleosynthesis during the explosion of a low-mass neutron star formed in a close binary system in the stripping scenario is considered. In the scenario considered the shock arising during the explosion is shown to strongly…
As electromagnetic showers may alter the abundance of Helium, Lithium, and Deuterium, we can place severe constraints on the lifetime and amount of electromagnetic energy injected by long-lived particles. Considering up-to-date measurements…
The effective number of neutrino species, $N_{\rm eff}$, serves as a key fitting parameter extensively employed in cosmological studies. In this work, we point out a fundamental inconsistency in the conventional treatment of $N_{\rm eff}$…
Prediction of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) is one of the three strong evidences for the big bang model. Precise knowledge of the baryon-to-photon ratio of the Universe from observations of the…
Primordial or Big Bang nucleosynthesis (BBN) is one of the three historical strong evidences for the Big-Bang model together with the expansion of the Universe and the Cosmic Microwave Background radiation (CMB). The recent results by the…
We discuss in detail the effect of neutrino oscillations in Big Bang nucleosynthesis, between active and sterile neutrinos, as well as between active and active neutrinos. We calculate the constraints on mixings between active and sterile…
We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…
Hot, dense plasmas exhibit screened Coulomb interactions, resulting from the collective effects of correlated many-particle interactions. In the lowest particle correlation order (pair-wise correlations), the interaction between charged…
We explore the effect of neutron lifetime and its uncertainty on standard big-bang nucleosynthesis (BBN). BBN describes the cosmic production of the light nuclides $^1{\rm H}$, ${\rm D}$, $^3{\rm H}$+$^3{\rm He}$, $^4{\rm He}$, and $^7{\rm…
Recently it is reported that there is the discrepancy between big bang nucleosynthesis theory and observations (BBN crisis). We show that BBN predictions agree with the primordial abundances of light elements, He4, D, He3 and Li7 inferred…
We study the impact on the primordial abundances of light elements created by a variation of the quark masses at the time of Big Bang nucleosynthesis (BBN). In order to navigate through the particle and nuclear physics required to connect…
We present calculations showing that upcoming Cosmic Microwave Background (CMB) experiments will have the power to improve on current constraints on neutrino masses and provide new limits on neutrino degeneracy parameters. The latter could…
Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. The recent results by the Planck satellite mission have slightly changed the estimate of the baryonic density compared to…
A massive long-lived tau neutrino in the MeV regime modifies the primordial light-element abundances predicted by big-bang nucleosynthesis (BBN) calculations. This effect has been used to derive limits on the tau neutrino mass. Because…
Systematic uncertainties in the light-element abundances and their evolution make a rigorous statistical assessment difficult. However, using Bayesian methods we show that the following statement is robust: the predicted and measured…
We have conducted fully relativistic simulations in a class of scalar-tensor theories with derivative self-interactions and screening of local scales. By using high-resolution shock-capturing methods and a non-vanishing shift vector, we…
We present a review of cosmological nucleosynthesis (CN) with neutrino oscillations, discussing the different effects of oscillations on CN, namely: increase of the effective degrees of freedom during CN, spectrum distortion of the…
Big bang nucleosynthesis (BBN) is the standard model theory for the production of the light nuclides during the early stages of the universe, taking place for a period of about 20 minutes after the big bang. Deuterium production, in…
Big Bang Nucleosynthesis (BBN) is very sensitive to the cosmological expansion rate. If the gravitational constant $G$ took a different value during the nucleosynthesis epoch than today, the primordial abundances of light elements would be…